[LL FIR] rename testdata to testData to avoid copyright generation

We exclude testData pattern from copyright scope

analysis/low-level-api-fir/testData/fileStructure/topLevelUnitFunScript.lazy.resolve.txt

@@ -0,0 +1,8 @@
+FILE: [ResolvedTo(BODY_RESOLVE)] topLevelUnitFunScript.kts
+    context(<script>@R|kotlin/script/templates/standard/ScriptTemplateWithArgs|)
+    SCRIPT: [ResolvedTo(BODY_RESOLVE)]
+        [ResolvedTo(BODY_RESOLVE)] lval args: R|kotlin/Array<kotlin/String>|
+
+        public final [ResolvedTo(BODY_RESOLVE)] fun foo(): R|kotlin/Unit| {
+            <Unresolved name: println>#(String())
+        }